The bottom line

■■ The number of billionaires on Forbes’ 35th-annual ranking swelled by 660 to 2,755 in one year. The billionaires’ combined fortunes increased to $13.1 trillion, up from $8 trillion last year, with the top 10 alone worth $1.15 trillion. Amazon’s Jeff Bezos kept the top spot for a fourth year, with a fortune of $177 billion.

Forbes

■■ Tesla delivered a record 184,800 vehicles last quarter. The sales beat estimates despite the fact that they include only 2,020 sales of Tesla’s Model X and Model S, which are waiting for updates to resume production.

AutoNews.com

■■ U.S. consumers spent an average of $138 on iPhone apps last year, an increase of 38 percent year over year. Roughly half of that— $76.80—was spent on games. Puzzle games such as Candy Crush Saga made up the biggest category, with $15.50 per active iPhone, followed by casino games, which averaged $13.10.

TechCrunch.com

■■ Once the world’s thirdlargest smartphone maker, LG said this week it is winding down its mobile division after six years of losses totaling some $4.5 billion.

CNBC.com

■■ A jump in mortgage rates over the past two months means that a typical buyer will spend an additional $93 per month on mortgage payments. That equates to roughly $1,100 per year, or about $33,000 over the life of a 30-year loan.

MarketWatch.com

■■ More than 9 percent of subprime borrowers with outstanding auto loans or leases were more than 60 days past due in the fourth quarter, the highest quarterly figure in data going back to 2005.

The Wall Street Journal